PGP Protocol Overview

PGP Protocol OverviewPretty Good Privacy (PGP) is both a protocol and the
name of the program that most widely implements that protocol.
The PGP protocol, documented in
RFC 1991,
is a presentation layer protocol that defines a standard
to cryptographically secure email messages.
RFC 2015 describes how
various kinds of PGP messages should be encapsulated using
MIME.